Would you recommend a a crf250f for a beginner dirt biker?

Well the CRF250 is a race bike intended for Pros and advanced riders, it has power that could be hard to control for a beginner, so for you to start I would recommend a TTR 125 or other 125 but then you want also Brother and father to ride same bike and the 125 could be too week for big/heavy guys. I would stay with TTR230 or crf230 which are fun to ride, affordable and powerful enough to carry brother or father. Don't get tricked by the numbers a CRF 230 has nothing to do with a CRF 250,even when seems to be close.